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Please assist me with the following; regarding the ME96SSHA-MB Power meter data transition with Melsec-Q series PLC;
We acquire to read various values on dedicated Modbus storage address registers at the simultaneous into a Melsec-Q series PLC via Modbus (TCP or RTU) for calculation purposes.
Naturally, since the reading of these variables are to provide accurate instantaneous results, it is a requirement that these values are to be read at one scan.
However, as can be seen below, there is a gap in address register range – of which, if all of these are scanned simultaneously, yields an exception error when read.
This error is only avoided by scanning these data sets separately – which is not ideal for our application – since accuracy in calculations is imperative.

i am using a VSD Altivar71 and controlling it through serial MODBUS communication, the probllem is sometimes after stoping the motor the drives gives the "nst" fault which means according to the programming catalouge "freewheel stop" it doesn't do that all the time but it happens a lot and after uploading the code again to plc the problem is gone for a while before it happens again. i am sure that the fault is happening because if communication because when i controll the drive from hmi it never gives that fault, i checked the setting and tried different cables but it still gives "nst" and motor never moves, i found that in catalouge but i am not sure how to address the problem.

Hi !
I have to Control and Read an Masss Flow Controller (MFC) MKS MF-1, I have give this one an IP Adress (10.46.103.75).
How can I Control it over Modbus TCP? I found in GX Works 3 in Tool/Predifined Protocol Support function the Modbus Menue, but i have no Idea
how to Config it, i have no Idea how Modbus works.....
Have someone an Example for a Configuration?

Hi,
I have R04CPU (iQ-R series) on one side and on the other side is QJ71MT91 (modbus tcp/ip module). Is it possible to make communication between them (QJ71MT91 is master and R04CPU is slave)? iQ-R series doesn't have Modbus TCP/IP module, but is it possible to set modbus tcp/ip on built-in ethernet port of R04CPU, and how?
Best regards
Luka

Does anyone have experience with a Jiskoot Insight controller? Im trying to establish communications between it and a MVI69-MCM. I have checked and rechecked all my settings. I am not sure what I am doing wrong.
Thanks

Hello,
I want control ATV320 inverter through MODBUS protocol. I found, that ATV312 inverter have IEC 61800-7 status chart. I attached picture. I want to ask, maybe ATV320 inverter have same IEC 61800-7 status chart and where need find it. Yesterday I try to find all evening, but don't successful. Somebody could help to me.

Hi all,
My Task: To control write to registers to my MSI430 safety PLC from Leuze Electronic using a HMI as a master.
Protocol: Modbus TCP
MSI430 (Modbus TCP - server/slave)
Generic HMI (Modbus TCP - client/master)
I'm reading Okay from the Register address 401101-40110
But I'm not able to write to the MSI PLC to address 402101-402109
Please see the attached images for gateway description for the device.
Please advice/guide on how this could be done.
I have tried using MBPoll and it says Illegal Data Address.
Kind Regards
NarkO
Please find the below link for the manual

HI, I HAVE FX5UCPU connected to other devices through built in RS485 port , i have gone through ADPRW instruction .To configure Slave devices like other third party controller , is there any special instruction required. i need few sample programs for modbus data transfer.

Hello,
I'm trying to make communication between a 315-2 PN/DP and MSA Gasgard XL.
I want to read out 40010, and 40020 from GasGard, it works sometimes, but most of time the connection does'nt build up.
The parameters i using are:
Start address: 9
Lenght: 10
Recv_Time: 5s
Conn_Time: 5S
I did playing with Recv and Conn Time and it effected the rate of succesful connections, but it still drops too often.
Also i tried to read only 9 and 19, but then it didn't read 19.
Anyone knows how could i optimize the connection?
Thanks

I'm looking at project with an OMRON NJ-101. I was planning on using Modbus TCP/IP from the PLC to talk to a MOXA gateway (MB3170) which would then talk to about 7 different slaves over RS-485. Looking at detail at the blocks that are supplied by OMRON (MTCP_NJ V1.3, available from https://www.myomron.com/index.php?action=kb&article=1245), I noticed that it doesn't send the slave ID, which will mean that it won't be able to talk to different slave ids through the one IP Address. I had a look through the actual code and it sends "FF" in place of the slave id. In particular I was looking at the "MTCP_Client_Fn03" block.
Is there another way to get the NJ101 to talk the full MODBUS TCP/IP protocol?
Is it possible to edit the blocks provided by OMRON? It seems to me that they are locked down. If I could edit it I could just add the functionality
Thanks for your help in advance.

Hello guys, i want to connect my CP1e-N30DT to modbus device like weighing scale, but i try to searching modbus with RTU but all of them use function block, i dont understand and i think my device cant use a function block.
Can you help me for connect CP1E to modbus device for get a holding register(4xxxx),input register(3xxxx), coil(0xxxx) and input status(1xxxx) with cx programmer? thank you

Greetings everyone,
I have a Proface HMI(LT-4201TM Modular type DIO) connected to a siemens flow transmitter(MAG6000). Communication between these two devices is using modbus.
The modbus register that im using to get the data/reading of a totalizer from siemens transmitter are 403022 and 403023. I managed to display the exact totalizer value from siemens transmitter on the Proface HMI screen.
But I couldnt get the exact totalizer value at the ladder logic side, the value that i get at the ladder logic side seems like a raw value.
For an example, the totalizer's value is 147083(real value), but at the ladder logic side the value for 403022=15598 and 403023=17316.
Can anyone guide me to solve this issue.
Thanks in advance.

hallo, i have problem here.
i want to connect HMI OMRON NB7W-TW00B to weighing indicator with Modbus RTU rs485.
i use this link https://www.myomron.com/index.php?action=kb&article=1538 for wiring diagram for rs485.
and the baudrate, databit, parity check and stop bit is same between HMI and weighing indicator.
but the output in HMI is "[2] PLC No Response: 00-01-2" i think the problem is my rs485 connection.
can you help me? thank you.

Morning Guys,
For my latest project I need to read a gas sensor via 485 from a Momentum PLC. I've been through the help files, but they seem to only raise more questions than they answer, they only seem to reference PLC -> PLC comms.
I've had a play with the 'MBP_MSTR' & 'OUT_IN_MBUS' function blocks, but i can't seem to get anywhere,
Has anyone got any examples of reading in data via 485, or can anyone lead me in the right direction?

Hello,
I wanna be sure before I'll spend some money, will I be able to control Turck devices (ie http://pdb2.turck.de/cz/DE/products/000000170000c8000003003a ), from I've found here on forum and on
internet it looks to me like it should be possible, but I'm new in field of automatization.
Thanks in advance
EDIT: I'm talking about Modbus

Hello everyone. I got the project where plc Q00UJCPU with the module QJ71MB91 connected to the slave device via 485 channel . This plc takes some values (like current/voltage etc). i dont have access to this plc cause he is on guarantee on another service company. So question is... How to connect to this device as a other plc FX3U via 485ADP-MB (and i think RS command) module in parralel to QPLC already working link? Is this possible without harm QPLC and all the data which he takes?

Hey guys I don't have much experience in PLC serial communication and I'm tasked to integrate 6 OP-905 scales with our EATON based control system. The scales are rs485 asynchronous serial communication, my concern is that if the device is not designed to be an RTU then I cannot use modbus. And if that is the case how do I talk to multiple scales using the async protocol. Has anyone done this in a similar platform?

I am developing an application with fx5u with inverter d700, it fails to send a command to the inverter, only running the application and monitoring the clp does not appear to fail, only when it sends a command. Attached photo of plc configuration and error. Do you have any secrets to doing communication, can I do it with a normal network cable? I'm doing with just one inverter, as the terminator should be at 110 or 330 ohm.

Hello everyone. I have Omron CJ2M-31 PLC with SCU32 communication unit, and 34 3G3MX2 drives with repeater. I use "Easy to use Modbus RTU Master for CP1L CP1H CJ1 CJ2 CS1" written by our member PMCR (thank you PMCR for sharing your experience). I need to reed VFD status, reset fault, and write the speed. I tried the sample code version 2.12 with a single VFD, but in my test application it works inconsistent. I had got communication in the first place, I could control the drive, but I lost it after program modification and downloading (I did not touch communication part). I was able fix communication only once, and lost it again. I didn't find any correlation between my action and communication presence ( I tested dual port program version). If the communication is present, SCU unit blinks fast, otherwise slow. I have cleaned PLC memory and initialized PLC without any luck.
Unfortunately, PMCR is offline. If anyone is proficient with mentioned above program, please advise where to look.
Thank you in advance.

I'm using Controllogix L61 redundancy system as a slave with DCS using ethernet tcp/ip socket programming. The communication between master and slave will fail after a switchover. Kindly give solution for this.
Thanks and regards,
Rasu

Hi.I would like to tell you about a modbus library I have made and recently released, for Siemens S7-1200 PLC's. I made concept that called Station block which is mapping of registers for one specific modbus rtu device. Station blocks can be made very quickly and can be easily be reused and combined with other station blocks. The library is free under the MIT-license and can be downloaded at github (link bellow). Please check it out, I would like to get some feedback on my work. https://github.com/olab84/rexhip/
An modbus rtu example:
#mb_master_ctrl(hardware_id := "Local~CB_1241_(RS485)",
baud := 19200, // bps
mb_query := #mb_query );
#mb_query(mb_addr := #mb_addr,
mode := #mb_query.c.read.input_reg,
data_addr := 13,
data_ptr := #resault_data_1);
#mb_query(mb_addr := #mb_addr,
mode := #mb_query.c.write.holding_reg,
data_addr := 55,
data_ptr := #resault_data_2);
// - The library will take care of execute each query, one by one.
// Add as many queries as need. (There no need of a state machine)
// - Queries belonging to one device can be placed inside one FB,
// this FB can later easily be reused.